Airborne life boat



y 1955 F. M. JOHNSON 2,707,600

AIRBORNE LIFE BOAT Filed Jan. 19. 1953 s Sheets-Sheet 1 .Jizs- E.

- INVENTOR. Fen/v05 M k177'N50/V BYW May 3, 1955 Filed Jan, 19, 1953 F. M. JOHNSON AIRBORNE LIFE BO!" 3 Sheets-Sheet 2 INVENTOR. FPH/VC/5/Z JOH JON U/Mu/ QLMWK HTTMNEYS (Granted under Titie 35, U. 5. Code (1952), sec. 266) Ciaims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to the automatic air-to-water delivery of airborne lifeboats by parachute and the quick sling-to-lifeboat release mechanism associated therewith.

The present practice of disconnecting the parachute from the sling shackle and dropping the sling and the accessories into the boat is fraught with much danger and it is therefore herein recommended that the sling be released from the lifeboat upon contact of the boat with the water, thus allowing he parachute to pull the sling clear.

The broad concept of air-to-water delivery by parachute is old in the art and some of the instrumentalities known and used in prior art are used in a dilierent way in the present invention.

It is a prime object of this invention to provide a system of delivery which, while it is especially adapted to air-to-Water delivery of life boats, is nevertheless applicable to other delivery systems.

I attain this and similar objects by a combination and arrangement of the several devices hereinafter shown and described, reference being had to the drawings wherein:

Fig. l is a view of a large carrying ship with a lifeboat shackled to the underside stern forward, means being provided to release and drop the lifeboat at a sufficient altitude above its final destination in the water.

Fig. 2 shows a lifeboat equipped with the instrumentalities which adapt it for use in the delivery system herein disclosed. The lifeboat in this view has been released from the carrier ship and dropped, and the parachute opened.

Fig. 3 is a left side elevation of my improved quick disconnect unit which is provided for freeing the lifeboat from the parachute and from the slings which attach the lifeboat to the parachute. This view shows the device when it is in its operative or locked-up position. One of the solenoids which trip the quick disconnect whereby it is moved from the holding to the release position is also shown in this view.

Fig. 4 is a rear elevation of the quick disconnect unit in its operative or locked-up position.

Fig. 5 is a bottom plan view of the quick disconnect unit also in the operative or locked up position.

Fig. 6 is a left side elevation of the quick disconnect unit similar to Fig. 3 but showing the unit in the inoperative or unlocked position.

Fig. 7 is a cross section through the unit, taken at 7-7 of Fig. 4.

Figs. 8, 9 and 10 are detail views of the side plates, the receiver and the dog respectively.

Fig. 11 shows the cable and stirrup which is preferably carried one at the lower end of each sling by the delivering aircraft. The stirrup is the upper member of the quick disconnect unit herein disclosed.

Like reference characters refer to like parts throughout the several views.

aired tates Patent 0 2,7h7,% Patented May 3, 1955 Referring to the drawings and more particularly to Fig. 1,.a large airplane 11 preferably a B-29, on its underside 13 is constructed and arranged with appropriate shackle means 15 to carry and drop a lifeboat 17. The stern 19 of the lifeboat is pointed forwardly. The shackle means 15 for releasing the lifeboat may be arranged for manual or power operation as desired.

Fig. 2 shows the lifeboat 17 to a larger scale than is shown in Fig. l, and still with stern pointed forward. The parachute 21 is shown open and supporting the load but while still packed may preferably occupy a space 23 shown in phantom in the midportion of the lifeboat. The shroud lines 25 are brought together at 29 and fastened to the upper end of the cable 27, the lower end 29' of the cable being adapted to be connected to the two slings 31, which, at the lower end, are secured to the lifeboat 17 by the quick disconnect devices hereinafter shown and described.

it is noted that one of the slings 31 is shorter than the other, whereby the lifeboat is tilted in such a manner that the trailing end will enter the water first.

At about the point where the lifeboat first strikes the water, a water impact operated diaphragm is mounted on the outside of the hull and is adapted to close the microswitch 33 upon contact with the water.

A source of electric current supply 35 energizes the movable arm of the switch 37 of a relay 39 and coincidentally energizes the coil of the relay whereby the switch 37 is closed. Current now energizes the solenoids S and S connected to the latch means for the quick disconnects 43 aud 51 whereby the quick disconnects 43 and 51, which Will be hereinafter described in detail, are tripped. 7

An electric line extends from the microswitch 33 through the relay 39 when closed to a solenoid S which is constructed and arranged to release the quick disconnect 43. A second electric line extends from the electric line aforesaid to a solenoid S which is constructed and arranged to release the other quick disconnect 51.

Referring now to the construction and operation of the quick release units which connect the slings 31 to the lifeboat 17, the mounting or bottom plate It) has two side plates 12 extending upwardly therefrom. The side plates 12 may be integral with the mounting plate or attached thereto by welding or other suitable means.

The side plates 12 are appropriately spaced apart to slidably admit a receiver 14 and a dog 16, the receiver and the dog being of the same thickness and both in the same plane and both freely slidable in the same space between the side plates. The side plates, the receiver and the dog are shown separately and in detail in Figs. 8, 9 and 10. One of the solenoids provided, to push against the lower arm of the dog 16 to trip it, is mounted on the underside of the deck While the quick release device which is operated by the solenoid is mounted on the top of the deck.

The receiver 14 is hinged between the two side plates 12 by a hinge pin 18 which is a close running fit in holes 20 and 22 in the side plates 12 and the receiver 14 respectively.

The side plates 12 each have a U-shaped slot 24 with curved sides extending upward, while the receiver 14 has a slot 26 of like width with sides extending horizontally. The width of the slots 24 and 26 at their respective bottoms may preferably be several one-thousandths of an inch greater than the diameter of the stud pin 56.

Holes 28 and 30 which extend through the side plates 12 and the dog 16 respectively receive the hinge pin 32 upon which the dog is rockable. The holes 28 in the side plates are centered on the same horizontal line as the radius of the bottom of the U-shaped slots 24 and 26 when the device is closed.

. A dog return spring 34 is compressed, the one end seated in a recess in the dog 16 and the other end seated in a recess in a small stud 36 which has been driven into a hole in the mounting plate 10.

A receiver actuating plunger 38 is slidable in a spacer block 4-. between the side plates 12, the plunger being actuated by a spring 42 to rotate the receiver clockwise through a small angle of rotation. A small rod 44 extends througn the two side plates 12, the part of the rod between the plates acting as a stop for the receiver 14 to keep it from rebounding beyond the desired limits when the device is operated to disconnect. A like rod 44' is positioned to act as stop for the dog to prevent it from overrunning when the device is tripped. A notch 46 on the upper end of the receiver 14 is engaged by a hook on the upper end of the dog 16 for holding the device in the cocked position. Shifting the lower end of the do 36 in the direction of the arrow 49 as seen in Fig. 3 trips the mechanism for release whether the shift is mechanically, electrically or hydraulically operated.

The device thus far shown and described in detail represents one of the elements of the quick disconnect, the other element being in the form of a stirrup 5d, Fig. ll, with cable 31 attached. The stirrup 5t) consists of a bar 54 being in the form of an inverted U, the bar being widened at the ends and bored to admit a stud S6 of a size which is preferably substantially equal to the hinge pin 13.

Quick connection is preferably made by keeping the axis of the stud in a horizontal plane and entering the stud 55 from above into the U-shaped slot 24 in the side plates 12 and pressing it downward so as to turn the receiver 1 5 anticlockwise about the hinge pin 18, and thereby remove the receiver hook 55 from the posi tion which it is seen in Fig. 6 to the position in which it is seen in Fig. 3.

Quick disconnection is made by rotating the dog 16 anticlockwise on its hinge pin 32 until the hook 48 releases the notch 46.

In operation the parachute canopy 21, shroud lines 25, cable 27 and slings 31 are packed in approved fashion in the space 23 in the lifeboat with the quick disconnects in the locked-up position.

When the shackles 15 on the airplane 11 are released,

the lifeboat It? first falls free until the break cord 53 tautens, causing the parachute to release and open, and the cord 53 breaks whereupon the canopy 21 falls free with the attached lifeboat and opens suspending the lifeboat as shown.

When the li eboat 17 strikes the water, water impact actuated microswitch 33 first, the solenoids for the quick disconnects 43 and 51 are operated and the quick disconnects 4-3 and 5.; are released, whereupon the lifeboat slides into the water and the parachute including the canopy 21, shroud lines 25, cable 27 and slings 31 are automatically released and fall into the water free of the lifeboat and may be expendable.

I claim:

1. Apparatus for launching an airborne lifeboat into a body of water, comprising a lifeboat adapted to be supported and released from a supporting aircraft while in flight having front and rear decks, a connected packed parachute therein for lowering the lifeboat from the carrier aircraft into the water including detachable connecting means between the parachute and the front and rear dccks of the lifeboat for suspending the lifeboat below the parachute in an inclined position during descent, electrically operable release means for releasing said detachable connecting means, water impact operated switch means on the bottom of the lifeboat at the lowest point where the lifeboat first contacts the water in said inclined position, including an electrical actuating circuit connected to said release means for actuating said release means immediately upon impact of said water impact operated switch means with the water, whereby to release the parachute from said lifeboat substantially prior to the entrance of the lifeboat into the water.

2. Apparatus for launching an airborne lifeboat into a supporting body of water, comprising a parachute for suspending and lowering the lifeboat into the water when released from a carrier aircraft, plural suspension sling means of unequal lengths adapted to incline downwardly away from each other for connection at longitudinally spaced points at the opposite ends of the lifeboat, and connected at their opposite ends to the parachute at a substantially common point below the parachute, for suspending a lifeboat during descent in a longitudinally inclined position, electrically simultaneously operable release means for the lower ends of said suspension sling means, adapted to be fixed to the opposite ends of the lifeboat to be lowered, an electrical release circuit connected to both of said release means for simultaneous release actuation thereof, a water impact actuated switch means in said circuit for closing said circuit, adapted to be fixed to the bottom of the lifeboat to be suspended and lowered at the lowest point thereon when suspended in said inclined position for closing said circuit to simultaneously release said parachute from the lifeboat upon impact thereof with the water before the lifeboat enters the water.

3. in an apparatus for launching an airborne lifeboat into a body of water comprising a carrier plane, a lifeboat having front and rear decks, a parachute releasably connected to the lifeboat to suspend the lifeboat therefrom during the descent of the parachute after release of the lifeboat from the carrier plane, a static break line connested at one end to the parachute and at its other end to said carrier plane for deployment of the parachute when the lifeboat is dropped from the carrier plane, said parachute connection to said lifeboat comprising a pair of supporting slings of materially different lengths connected at their upper ends at a substantially common point below the parachute and inclining downwardly away from each other with their lower ends detachably connected to the opposite ends of the lifeboat to suspend the same in a materially longitudinally inclined position below the parachute during descent, said detachable connections including a pair of electrically operable disconnect sling securing means, one fixed to each of said front and rear decks of the lifeboat, each disconnect comprising a base plate fixed to the top of one of the decks, a pair of spaced parallel side plates extending upwardly from said base plate and formed with aligned curved entrance slots extending downwardly from the tops of the side plates terminating in a sling receiving opening, a sling retaining member pivoted between the side plates on an axis perpendicular to the side plates, located below the bottom of the sling receiving recess, said sling retaining member having an arm portion ex tending laterally from one side thereof across said entrance slot above said sling receiving recess, when said retaining member is in operative position, spring means between the sling retaining member and said base plate for swinging said retaining member and arm out of said entrance slot, a latch member pivoted between the side plates at one side of the entrance slot having a hook portion engageable with the outer end of said arm when said retainer is in operative position, spring means between said latch member and said base plate urging said latch member hook portion into latching engagement with the outer end of said arm, magnet means fixed below said base plate for disengaging said latch member from said arm, an electrical energizing circuit for said magnet means including a switch in said circuit and water impact actuated means for closing said switch means located on the bottom of the lifeboat at the lowest point thereon when in said inclined suspended position for impact with a body of water below the lifeboat during its descent prior to the entrance of the lifeboat into said water.

4. In a quick disconnect mechanism for releasing an airborne lifeboat when suspended from a sustaining parachute prior to delivery thereof in a longitudinally inclined position into a body of water, a parachute, a pair of supporting slings of unequal lengths extending from the parachute below the center thereof to the opposite upper ends of the boat for sustaining the boat in said inclined position, a water impact actuated switch means located at the lowest point on the bottom of the boat when in said inclined position, an energizing circuit including said switch means, a pair of quick disconnect mechanisms connected in said circuit for simultaneous actuation fixed to the top of the opposite end portions of the boat, releasably connecting the lower ends of said slings to the ends of the boat, said quick disconnect mechanisms each comprising a base plate fixed to one of the said ends of the boat, a pair of spaced side plates projecting upwardly from said base plate in spaced parallel relation, said side plates having aligned curved elongated entrance openings formed therein for receiving the lower end of one of said slings, said sling ends each comprising a clevis member having a cylindrical pin therein, said entrance openings inclining downwardly from the upper ends of the side plates at points adjacent one edge thereof terminating in aligned semicircular bottom portions for seating the clevis pin therein, a retainer plate pivoted be tween said side plates on a fulcrum located intermediate the semicircular bottom portions of the entrance openings and said base plate, said retainer plate being swingable between a sling retaining position extending across said entrance opening and a receiving position, and

formed with an elongated sling end receiving opening extending laterally partly across said retainer plate intermediate its outer end and its fulcrum terminating in a semicylindrical bottom formed to dispose the receiving opening therein in register with the side plates entrance opening when in said receiving position and to dispose the said semicylindrical portion in register with the semicircular bottom portion of the side plates openings with said retainer plate entrance opening out of register with the side plates entrance openings when in said retaining position, an elongated locking dog pivoted between said side plates at one side of said retainer plate having a hooked outer end arranged for latching engagement with the outer end of the retainer plate when the same is in said retaining position, said locking dog having an actuating lever portion extending through and below said base plate, magnet means located below said base plate for moving said locking dog to release position, spring means for moving said dog to locking position, and spring means for moving said retainer plate to said receiving; position when released by said locking dog.

5. In a quick disconnect mechanism for airborne lifeboats of the class described, a base plate for mounting said mechanism, a pan' of spaced apart parallel side plates extending upwardly from said base plate, said side plates having a similar U-shaped sling receiving opening formed therein curving downwardly from the tops of the side plates near one of their side edges, terminating in aligned semicircular bottom portions having centers located substantially midway between the opposite side edges of the plates for receiving a clevis pin therein attached to the lower end of a supporting sling member, a retainer plate pivoted between the two side plates on a fulcrum located below the semicircular bottom of the recess and above the said base plate and swingable to an operative retaining position across said U-shaped opening to close the entrance thereof and swingable in the opposite direction to a position toward one side of said U-shaped opening to a release position, spring means urging said retainer plate to said release position, said retainer plate having a substantially transverse U-shaped sling receiving open ing therein extending partly thereacross from one side edge toward the opposite edge and terminating in a semicircular bottom portion for seating the clevis pin aforesaid therein with the axis of the semicircular bottom portion thereof in alignment with the axis of the semicircular bottom portions of the side plate when said retainer plate is in retaining position with the entrance to said retainer plate receiving opening out of register with the U-shaped opening entrance in the side plates, said retainer plate being movable to said retaining position with the entrance opening therein in register with the entrance of the U-shaped openings in the side plates out of register, a locking lever pivoted between said side plates intermediate the semicircular bottoms of the recesses therein and the side edges of the side plates adjacent the entrance to the U-shaped opening in the retainer plate when the latter is in retaining position, said locking lever having a hook portion at its upper end disposed for latching engagement with the outer end of the retainer plate when the retainer plate is in said retaining position and having an actuating stem portion extending downwardly through and beyond said base plate, for moving said locking lever to disengage said hook portion from said retainer plate, spring means connected to said stem portion for moving said lever hook portion into latching engagement with said retainer plate.

References Cited in the file of this patent UNITED STATES PATENTS 272,253 Hill Feb. 13, 1883 2,382,442 Rich Aug. 14, 1945 2,545,248 Winzen Mar. 13, 1951 FOREIGN PATENTS 429,633 Italy Feb. 2, 1948 

